Why is avast not working on my Samsung S9 anymore?

General
1

Why is avast not working on my Samsung S9 anymore

2

First, I’m an Avast user and not an Avast Team member.

There really is no information to attempt to answer.
In what way isn’t it working any more, e.g. are you getting any error messages, etc. ?
What Avast Mobile version number and what Android OS version on your Samsung S9 mobile ?

This would probably have been better placed on the Avast for Mobile sub-forum